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By C. B. Manula

Simulation continues to hold the spotlight among the Operations Research applications in the operational side of mining. One reason for this is the need to solve the many waiting line and storage problems common to the industry. A second reason for using simulation is the central requirement of retrospect testing. Acceptance of a model by management is more likely to depend on its tested performance rather than on the underlying validity aspects of the model itself. Mathematics have not been and may not be developed that will allow all desired system elements to be considered simultaneously. It is in this realm that simulation bridges the gap between theory and useful design procedures. One of the earliest published accounts of simulation at work in the coal industry is demonstrated by the application cf Monte Carlo methods to explore changes in future operating policies for an existing track system (Manula, 1963). By modifying certain control parameters, revision in design changes were evaluated in the computer rather than in the actual production section. A second application which has found wide use in practice is the VFI-OCR Face Simulator (Prelaz et al., 1968). The model developed here has the purpose of allowing the comparison of methods for room-and-pillar face operations end observing their effect on mining prior to actual installation. Proposed changes are tried in the model and the best of these are selected as a guide for better mire management: IBM's own simulation package, the System 360 General Purpose Simulator, has experienced heavy use in solving similar problems and other steady-state situations.

Jan 1, 1974

By James Weaver

During the past 16 years, the authors have successfully used high-capacity rock anchors installed inside open-ended pipe piles, driven to bedrock, to provide uplift and overturning resistance for various structures including piers, bridges, power plant components and commercial buildings. These systems were ultimately used on the projects due to a combination of high uplift forces or overturning moments on the structures and the relatively poor subsurface conditions present at the sites. Other, foundation systems such as rock-socketed drilled shafts and spin fin piles were considered but were found to be economically prohibitive or not technically feasible.

Jan 1, 2011

By A. Sariisik

This study analyses the results of a pilot trial of a newly developed armed-chained stone-cutting machine. The machine was developed in Turkey and trialed at the Kaklik/Kocaba travertine quarries in the Denizli District. An armed-chained cutting machine is an alternative to the diamond wire cutting method more frequently used in the production of natural stone quarry blocks, and increases production efficiency and quality. Since there is no need to collapse the blocks using the armed-chained cutting production process, there is no risk of the block developing cracks. This results in a considerable increase in the efficiency of natural stone block production. The armed-chained cutting machine is easier both to assemble and run when compared to other block cutting methods. This process resulted in the production of a larger number of blocks at a lower cost within the same time frame, particularly in travertine quarries and in all other natural stone quarries. The block efficiency in travertine quarries was calculated as 65?80%using the armed-chained cutting machine, compared with 7?14% using the normal diamond wire cutting method.

Jan 1, 2010

By D. Bienstock

As part of the development of the hot-carbonate scrubbing process by the Bureau of Mines, the corrosion rates of steel in boiling solutions of potassium carbonate saturated with carbon dioxide and hydrogen sulfide were determined, and the effectiveness of various inhibitors was evaluated by Bureau researchers. The highly corrosive solution of carbonate saturated with carbon dioxide can be inhibited with a 0.2-percent concentration of either potassium chromate or sodium metavanadate. Solutions of carbonate saturated with carbon dioxide and hydrogen sulfide are mildly corrosive, 0.01 inch per year. Complete absence of corrosion is obtained with 0.2 percent sodium metavanadate or 0.15 percent vanadium pentoxide. Oxidizing inhibitors such as potassium chromate are destroyed in the alkaline sulfide mixture, N-alkyl trimethylene diamines, at a concentration of 0.1 percent, lower the corrosion rate to about 0.005. Sodium metasilicate, at a concentration of 0.6 percent, completely inhibits the corrosion but may deposit free silica in the system. Commercial cladding materials such as the epoxy coatings also prevent corrosion.

Jan 1, 1962

By Sylvain Létourneau

Help organizations maximize the benefits of the data that they collect ? perform scientific research in: machine learning, data mining, statistics, artificial intelligence, soft computing, information retrieval, information systems, and natural language processing ? preferred application areas: Equipment Health Management, Bioinformatics, Health, Web Mining ? today?s talk limited to Equipment Health Management While the aircraft is still in the air, IDS: ? clusters relevant WRN, FLR, and snag (pilot) messages ? identifies probable causes based on TSM and provide links to corresponding TSM pages ? assesses MEL conditions (GO, NOGO, GOIF, ?) ? displays relevant maintenance history, suggests fixes based on similar cases ? Commercialization with MxI Technologies Ltd and Air Canada in 2000

May 1, 2008

By Lulie H. Crump

Salient information on reserves, production, and consumption of fuels and energy by State is summarized in this Bureau of Mines publication. Reserve and production data are shown for each of the fossil fuels (coal, crude oil, natural gas liquids, and natural gas) and for uranium. The consumption data of each of the major consuming sectors (household-commercial, industrial, transportation, electric power, and miscellaneous) are broken down by energy source (coal, petroleum, natural gas, hydropower, and nuclear). In addition, total energy consumption in the Nation in 1974 is compared with consumption in 1973 and 1975 (preliminary data).

Jan 1, 1977

By L. W. Higley

It is estimated that well over 20 million lb of chromium and 8 million lb of nickel, plus other metal values, are diverted annually to furnace dusts, mill scale, and contaminated swarfs in the domestic stainless and other specialty steelmaking industry. Little inroad has been made toward the in-plant recycling of these wastes to reclaim the metal values. The Bureau of Mines has devised a process for recovering about 90 pct of the chromium and molybdenum and well over 90 pct of the nickel and iron from stainless steelmaking furnace dusts, swarf, and mill scale. Other metals such as manganese are also recovered. Initial laboratory results were confirmed and expanded to include a wide variation of stainless steelmaking waste mixtures. Later experiments have included specialty steelmaking wastes other than from stainless steelmaking. Significantly, the ease of technology transfer has been demonstrated by a number of industrial-sized (19-ton) commercial electric furnace heats, in which the pelletized wastes represented some 10 to 20 pct of the furnace charge, replacing part of the normal scrap charge. Results of these successful large-scale trials are presented. Some information is also presented on incorporation into the pellets of chromium-bearing particulate wastes originating from other than steelmaking production. Cost evaluation indicates the process is economically attractive.

Jan 1, 1982

By H. J. de Haan, L. Schenk

Scope for Thermal Recovery in Shell's Heavy Oil Fields in Venezuela The main heavy oil reservoirs on the East coast of Lake Maracaibo (Fig. I), known as "Bolivar Coast", initially contained some 20 billion bbl of oil in place with gravities in the range of 10 to 15° API. The current total production rate is about 400,000 B/D. Since the recovery to date is on an average only 12.5 percent of the initial oil in place, these fields offer a vast potential for secondary recovery methods. The reservoirs are characterized by moderate depth (generally 1,000 to 3,000 ft; maximum 5,000 ft), good formation properties such as net oil sand thickness (50 to 300 ft), high porosity (30 to 40 percent) permeability (1 to 3 darcies) and oil saturation (initially about 80 percent) and high oil viscosity (100 to 10,000 cp in situ), all of which are favorable for the application of thermal recovery processes. Since 1957, steam drive, steam "soak" and underground combustion have been tested or are being tested in this area.1-3 This paper deals with a major steam drive test in the Tia Juana field. The test was commenced in Sept., 1961, on the basis of encouraging results of laboratory experiments and pilot field tests, which will be discussed briefly. Early Laboratory Investigation of the Steam Drive Process In 1956 a series of model experiments was carried out in the Koninklijke/Shell Laboratorium, Amster- dam, to investigate the displacement of heavy oil by steam.' The prototype studied was a horizontal, un-consolidated heavy oil reservoir, subjected to a linear steam drive. The model, representing a slab from this reservoir along the main flow direction, consisted of a steel tube filled with oil-saturated sand, provided with layers of rock at the top and bottom to simulate conductive heat losses to cap and base rock. Lateral heat losses, perpendicular to the main flow direction, were minimized by insulating the sides of the model. Heat flow and viscosity and gravity forces were scaled by taking the steam injection rate and sand permeability inversely proportional to the geometric reduction factor of the model, and using materials (oil, steam, cap rock, etc.) identical with those of the prototype. The main feature of the process was a frontal displacement mechanism that was observed within wide ranges of injection pressure and rate, oil viscosity, initial oil saturation and sand permeability. The high stability of this front can be attributed to the high volumetric steam flow rates, combined with the reduction in oil viscosity. High recoveries were obtained due to the low residual oil saturation of about 15 percent in the zone swept by steam. The latter value pertains to the specific test conditions (heavy oil, uncon-solidated sand) and may be lower for light oil, due to the effects of steam distillation. The applicability of this experimental approach is limited, as it does not take into account the fact that

Jan 1, 1970

By M. Jayaraman

With the ever increasing demand for commodities, due to changes in lifestyle and increase in population, people are striving to find ways to keep up. Mining is one essential element in the solution. Though being a powerful boost to a country?s economy, mining can have disastrous effects in the absence of waste management practice and technologies; because of the harmful heavy metals and toxic chemical waste that is generated as a by-product in mining operations. It is an established and documented fact that pollution is a major concern for communities having to live with it. Disproportionate water consumption significantly impacts local rivers and ponds thereby reducing freshwater availability and have given rise to social conflict. In light of these misgivings, management and treatment of mine water and waste has gained considerable attention recently. In this paper, we summarize some of the treatment methods that can be adopted by mining companies to reduce their environmental footprint. Appropriate treatment solutions depend on various factors including available space and capital cost for treatment solutions, type of mining waste generated, current state of the mining plant, geographical location, and other location specific issues. Incorporating waste and water management solutions as a priority within mining operations is critical for addressing increasing regulatory requirements and a starting point for initiating other Corporate Social Responsibility (CSR) programs. Collaboration among mining companies, NGOs, local community, and government facilitates successful projects which build trust leading to long term relationships. In this paper we also talk about the benefits of implementing a CSR project that captures the focus of local communities and allows the mining company to focus on operations. Implementing a sustainable business model that incorporates the broader community impacted by projects will continue to benefit even after the mining company ceases operation in that location. The challenges involved with implementing effective CSR projects, which require measuring and reporting effectiveness to create a positive social, economic, and environmental impact is also presented in this paper.

Aug 1, 2013

By R. R. Lowery

This project was proposed to provide information on the hazards associated with arc melting of thorium. A general air-sampling analysis was made to determine the separation, concentration, and distribution of thorium daughter (decay) products throughout arc melting, machining, and forging processes of a thorium handling facility. The value of well coordinated health physics program is stressed in connection with potential health hazards and personnel protection. Building, equipment, and exhaust ventilation requirements for such a facility are discussed. Special handling methods are described for thorium. INTRODUCTION The Bureau of Mines at the Albany Metallurgy Research Center has been involved in handling the naturally radioactive metals, uranium and thorium, for several years. Cooperative work for the Atomic Energy Commission has been carried out with thorium metal, and as a result the concerned laboratories of the Center have accumulated experience on the hazards associated with this metal. This report details the radioactive hazards arising from the arc melting, machining, and forging of thorium.

Jan 1, 1962

By J. Kendall Hales

Jan 1, 2005

By Edward L. McHugh, Louis J. Denes, Jami M. Girard

A prototype portable hyperspectral imager that operates in the visible and near-infrared ranges of the electromagnetic spectrum was field tested at an open-pit mine. The tests were sponsored by the Spokane Research Laboratory, National Institute for Occupational Safety and Health, as part of an investigation of remote sensing technologies for use in detecting and monitoring conditions in surface mines that could lead to catastrophic slope failure. The spectro-polarimetric imager, built at the Carnegie Mellon Research Institute, employs an acousto-optical tunable filter (AOTF) to control wavelength, a phase retarder to measure polarization signatures, and a digital camera and computer to capture data. The spectral range of the instrument is 450 to 1000 nm at 10-nm intervals. High-resolution hyperspectral images of highwalls, outcrops, hand samples, and drill core were collected in the field. Spectra from the images closely matched those of specific minerals present and were used to classify the images. The field tests were designed to examine the feasibility of using spectral imaging to assist in compiling objective geologic maps of mine highwalls and other hazardous slopes. Results illustrate the capability of the method to discriminate materials within the image, validating the concept of simplified spectral imaging. A contributing factor in many slope failures is the presence and distribution of mechanically incompetent, clay-rich altered rock in slope faces. Spectral features of clays and other minerals are more distinctive in the short-wave and mid-infrared part of the spectrum; the capabilities of the instrument need to be extended into this range to apply the AOTF-based technology to common geologic materials. A field-portable hyperspectral imager could find broad application in remotely identifying diverse materials from solids and coatings to gases.

By A. R. T. Denues

Liquid oxygen explosives are ordinarily made from a carbonaceous absorbent and from liquid oxygen of high purity. These explosives have a limited but definite field of usefulness; their properties have been described in the literature, which includes several publications of the Bureau of Mines, the most recent dealing with fire-retardant treatments.3/ It seems generally conceded that the outstanding hazards in the use of these explosives are their high inflammability and their relative sensitivity to mechanical action. Each of these topics has been studied, and some interesting practical results have been obtained. Treatments have been described[7] that render liquid-oxygen explosives prepared from granular carbonaceous absorbents practically immune to the action of igniting agents representing or exceeding practical hazards in violence.

Jan 1, 1941

By L Langer, R Simcock, M Davis

Rehabilitation of mining sites helps to achieve the purpose 5(2c) of The Resource Management Act 1991 û æavoiding, remedying, or mitigating any adverse effects of activities on the environmentÆ. The environmental outcomes for recent and current mining operations on the West Coast are variable. There are some exemplary mining operations which are restoring or even improving land use and environmental factors in the region, particularly those operated by the larger mining companies. There are also examples of an exploitative mentality where the environment and land have been severely degraded by mining activities. Technology has been developed to prevent a repetition of the historical destruction of the environment through mining. Failure to rehabilitate mined land is no longer acceptable to the New Zealand public in the 1990s and damages the credibility of the mining industry. Examples of successful mine site rehabilitation to pastoral farming and to production or plantation forestry are illustrated from the alluvial gold mining industry. Planning, sequencing of operations, the utilization of sailor plant growth materials, and aftercare are key factors in successful land rehabilitation to these productive uses. There is also a recent focus on restoring indigenous forests and wetlands at both coal and gold mining sites, particularly for mines on or adjacent to the conservation estate. The results of scientific research and efforts by the industry on techniques for rehabilitating rainforest and pakihi wetland after mining are presented, particularly from the Giles Creek Dunoille Coal Mine. There is a need for further research and trials to apply and extend rehabilitation techniques to other geological and environmental situations, particularly to mines in mountainous areas and to difficult environments like the coal measures ecosystems of the plateaux above Westport.

Jan 1, 1996

By R. Hart

In this paper, problems that have been experienced with the rockpass system at Kloof Mine No. 3 Shaft are described. Actions that have been taken to overcome the problems are also described. These include the use of slugshots to remove hang-ups, the abandonment and waste filling of passes, and design criteria adopted for an alternative pass system.

Jan 1, 2006

By Luke Erickson

San Francisco Public Utilities Commission is planning to replace 5 miles of pipeline under San Francisco Bay. The tunnel will be constructed using an Earth Pressure Balance (EPB) TBM and will be the first TBM-driven tunnel under the Bay. The alignment passes under environmentally sensitive habitats, through interbedded layers of sands and clays, and through a buried bedrock ridge. This paper discusses the geotechnical characterization and anticipated tunneling conditions and presents the analysis of various construction methods that resulted in the selection of an EPB TBM. Considerations related to tunneling with an EPB TBM are described in detail, including ground conditioners, TBM cutterhead wear, muck control, and squeezing ground.

Jan 1, 2008

A good deal of experimental work has been done from time to time on the application of compressed air to the elevation of wet pulp. On account of the flat nature of most of our mill sites elevation of the pulp has to be provided for, and the various methods in vogue show considerable loss of time, in the replaceing of wearing parts. During the last two years the writer has carried out a great many experiments with a view of devising an elevator that will give continuous work with a minimum of wear.The results do not show a high efficiency for the power employed, but the lift is continuous in operation, very cheaply installed, and possesses no wearing parts. The lift was tried working in a bore hole of 8 in. diameter, but in many cases it is more convenient to sink a small well for the purpose. The result to date showed that the most efficiency was obtained when the depth of the wellwas not less than the height of the lift required. The pressure of air required in pounds per square inch was (approximately) half the number of feet to be lifted.In the majority of cases the lift required varied between 20 ft. and 50 ft. and the air pressure required between 10 lbs. and 25 lhs. per square inch. In most existing installations the air compressors in use were delivering air to the receivers at about four times that pressure, and when air so compressed was expanded to perform its work at a reduced pressure, it was apparent that the power exerted in origInally compressing the air above the working pressure required at the lift was absolutely lost.

Jan 1, 1901

By Link. Theo A.

Introduction Since the discovery of a major oil pool at Leduc, Alberta, on February 13th, 1947, the long spell of 'oil drought' in Western Canada is now being turned into an oil and gas flood which requires immediate action to obtain the optimum economic benefits. The Woodbend, Section 9, and Okalta extensions of the Leduc field itself have been established; the Redwater pool, lying thirty-seven miles northeast of Edmonton, has been discovered and is being drilled up, and the Imperial Schoepp No. 1 or Golden Spike discovery holds promise of something phenomenal in view of the 500 feet of oil-saturated coral-reef porosity whose areal extent is not known. Imperial Stanolind Barrhead No. 1, northwest of Edmonton, revealed the presence of oil in the Madison, and just recently Gulf N.J. Ellis No. 1, some sixty miles southeast of Leduc, found commercial production in the Leduc D-2 discovery zone. In addition to these Paloeozoic discoveries, gas and oil reserves have also been established in the Upper and Lower Cretaceous, which must be penetrated by all tests on the way through the geological column to the Devonian. If ever there appeared to be an index of 'things to come' in the oil industry, this is it. However, without these recent discoveries the picture in Western Canada does and always did, look very promising indeed. A brief survey of the geological setting in Western Canada is the object of this contribution.

Jan 1, 1949

By Klaus Rieker

Over the last 30 years Wayss & Freytag Ingenieurbau AG has gained a lot of experience in mechanized tunnelling on various major projects. During this period most important developments concerning the machine technology for EPB- and Slurry-Shields have taken place. Since the first application of a hydro shield for the Wilhelmsburg Collector project in Hamburg in the early seventies, several stages of development have led to the current state-of-the-art in mechanized tunnelling. The continuous improvement of TBM techniques allows the execution of high quality tunnelling, particularly with regard to maximum safety and efficiency. The practical experience of the construction companies is of essential importance in order to continue further development and improvement.

Jan 1, 2005

By Raymond P. Miller

This two volume report addresses slope stability of surface mine spoils within the Interior Coal Province. Sixteen (16) mines were visited, pertinent data and samples collected, and reported spoil instabilities back-analyzed. Laboratory test results are compared to back-analyzed material properties. Available methods of slope stability analysis are reviewed and evaluated with respect to application to mine spoil stability evaluation and prediction. Correlation and tentative relationships among spoil material properties, highwall conditions, mining equipment and procedures and empirical observations are presented. Slope stability sensitivity plots illustrate the relative significance of various input parameters on stability. Slope stability input parameters are correlated with site and mining conditions to identify the primary factors controlling spoil stability. Investigative methods, spoil stability enhancement techniques, spoil stability prediction procedures and future study areas are discussed. Appendices include a glossary of terms, annotated bibliography, details of mine visits, and detailed laboratory test procedures and results.

Jan 1, 1979